Nowakowski, Grzegorz S.

Abstract Abstract 1572 Background: The incidence of histologic transformation (HT) of follicular lymphoma (FL) to an aggressive lymphoma has been reported to range from 10–75%. The British Columbia Cancer Agency reported a risk of 3% per year (Al-Tourah AJ, et al J Clin Oncol 2008;26: 5165–5169). The hallmark of HT is the acquisition of new somatic mutations and genomic instability within the malignant clone. DNA damaging agents such as radioimmunotherapy (RIT) may increase the risk of HT by inducing additional DNA damage. The incidence of HT after RIT is unknown. This single institution study analyzes the risk of histologic transformation (HT) in patients with FL after RIT treatment with yttrium-90 ibritumomab tiuxetan. METHODS: The Mayo Clinic Lymphoma Data Base were queried for all patients having received a single dose of yttrium-90 ibritumomab tiuxetan for FL. The Mayo Clinic Lymphoma Database includes all consecutive adult patients diagnosed with lymphoma evaluated at Mayo Clinic Rochester. The prospective radioimmunotherapy lymphoma database was also utilized (GAW). The diagnosis of FL was defined by current WHO Classification, and all cases were centrally reviewed. HT was defined as the development of histologically proven diffuse large B cell lymphoma in patients with history of Grade 1 or 2 FL (change to Grade 3A/B FL was not included). Patients having demonstrated evidence of HT prior to RIT were excluded from this analysis. RESULTS: 119 consecutive patients were included. 64(54%) were male. The median follow-up was 57(range 2–175) months. RIT was administered as treatment for progressive FL in 96.6% of patients. RIT was administered as a consolidation therapy in 4(3.4%) patients. The median number of prior systemic treatments was 2 (range 0–10). The median time from diagnosis to RIT was not different in patients with HT vs. those without HT 44 (10–186) vs. 40 months (range 1–394) (p=0.30), respectively. The median time to HT from RIT was 13 months (range 1–97). Four patients had HT within 3 months of RIT. The median survival after HT was 15 months (range 1–147). The estimated five year risk of transformation from RIT by Kaplan-Meier in patients with fludarabine exposure and those without exposure was 55% and 29% (p=0.0498). 10 year risk from the time of RIT was 64% with fludarabine exposure and 31% without (p=0.0498). The relative risk of HT after RIT in patients previously treated with fludarabine was HR=4.1 (95% CI: 2.0–7.9). The median number of prior therapies in patients with HT vs. patients without HT was 2 (0–6) and 1 (0–10) (P=0.33). CONCLUSIONS: To our knowledge, our data is the first to estimate the risk of HT after the use of RIT. The estimated overall risk of HT of 31% at 10 years from diagnosis in patients without fludarabine exposure is similar to that of patients in whom RIT has not been administered. The estimated overall risk of HT of 64% in those patients having received purine analogues appears to be increased. We conclude that RIT appears to not increase the risk of HT in patients who did not receive prior purine analogue therapy. The differences in extent and mechanisms involved in DNA damage induced by radiation vs. purine analogues may play a role in clinical differences in observed rates of HT. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 4136 Background: The serum free light chain (FLC) assay quantitates free kappa and free lambda immunoglobulin light chains. This assay has prognostic value in MGUS, multiple myeloma (MM), solitary plasmacytoma, and amyloid light chain (AL) amyloidosis, and has been incorporated in response criteria for both MM and AL amyloidosis. We previously showed elevated FLC was associated with poor outcome in diffuse large B-cell lymphoma (DLBCL) patients from a phase II cooperative group clinical trial (Blood (ASH Annual Meeting Abstracts) 2009 November 20, 2009; 114(22): 136). Here we replicate those findings in a large clinic based epidemiology cohort, as well as examine FLC abnormalities in other lymphoma subtypes. Methods: Newly diagnosed lymphoma patients were prospectively enrolled in the University of Iowa/Mayo Clinic SPORE Molecular Epidemiology Resource (MER). Serum FLC was quantitated from enrollment research serum draws within 9 months of diagnosis using the Freelite FLC assay (The Binding Site, Ltd., Birmingham, UK). Elevated FLC was defined as either kappa or lambda above the published reference range. Monoclonal elevated FLC was defined as elevated FLC with an abnormal FLC ratio; polyclonal elevated FLC was defined as elevated FLC with an FLC ratio in the normal reference range. Clinical data was abstracted using a standard protocol for the MER and patients were followed systematically for event-free (progression, retreatment, or death due to any cause) and overall survival (EFS and OS, respectively). Cox proportional hazards models were used to evaluate the unadjusted association between FLC and outcome. Results: 1118 lymphoma patients diagnosed between September 2002 and February 2008 with available serum were assayed. At a medium follow-up of 49 months (range 1–94), 484 patients (43%) had an event and 249 patients died (22%). Elevated FLC was present in 27% of lymphomas, with prevalence ranging from 13% in follicular lymphoma (FL) to 64% for mantle cell lymphoma (MCL) and 77% for lymphoplasmacytic lymphoma. Elevated FLC was present in 27% of DLBCL and associated with poor EFS (monoclonal hazard ratio (HR)=2.56, polyclonal HR=1.99, all p<0.001) and OS (monoclonal HR=3.22, polyclonal HR=2.91, all p<0.0001), replicating our previous findings. Elevated FLC was generally polyclonal (FLC ratio normal) across lymphoma subtypes, though monoclonal elevated FLC (FLC ratio abnormal) was common in MCL and the post-follicular lymphomas. Elevated FLC was associated with inferior EFS in all lymphomas combined (monoclonal HR=1.92, 95% CI:1.44-5.55, polyclonal HR=1.38, 95% CI:1.09-1.74); this association remained consistent in most subtypes (see table). In addition, elevated FLC was associated with poor EFS in MCL (monoclonal) and Hodgkin lymphoma (HL; polyclonal). Elevated FLC was also significantly associated with OS in HL (polyclonal HR=6.24, 95% CI 2.44–15.9), FL (polyclonal HR=5.85, 95% CI 2.62–13.0), post follicular lymphomas (polyclonal HR=4.16, 95% CI 1.17–14.8), as well as for all lymphomas combined (monoclonal HR=2.24, 95% CI 1.52–3.29, polyclonal HR=2.33, 95% CI 1.74–3.11). Conclusions: A significant percentage of lymphoma patients have elevated FLC. Our previous discovery of elevated FLC predicting poor outcome in DLBCL was confirmed in a large, independent dataset. Prevalence and type of elevated FLC (monoclonal vs. polyclonal) varies by lymphoma subtype. Elevated monoclonal and polyclonal FLC is associated with poor outcome broadly in lymphoma, as well as specifically for a number of lymphoma subtypes, supporting FLC as a potentially useful prognostic biomarker in many lymphoma subtypes. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 3575 Unconjugated monoclonal antibodies (MoAb) have proven value in the therapy of CLL, and alemtuzumab (ALEM) has efficacy in patients with purine analog refractory/p53 defective disease. Although the mechanisms of action of ALEM in vivo are not fully defined, complement dependant cytotoxicity (CDC) appears to play an important role. ALEM CDC resistance in a subpopulation of CLL cells in vivo could thus contribute to treatment failure. We hypothesized that the CD20 targeted complement activating human MoAb ofatumumab (OFA) would increase complement activation (as manifested by C3b deposition) as well as CDC in CLL cells treated with ALEM in vitro. Methods: We have completed experiments on 4 of 15 specimens collected from patients with progressive untreated CLL. CLL cells were isolated from blood by density gradient centrifugation and negative selection with magnetic beads. CD52 and CD20 expression were measured with fluorescent beads (Quantum MESF, Bangs Laboratories, IN). CLL cells were treated at a concentration of 2 × 106/ml with 10 mcg/ml of ALEM (Genzyme) and/or OFA (G.S.K.) in AIM V medium (Invitrogen CA) and 10% standard normal human serum (NHS) (Sigma, MO) as a source of complement for 1 hour at 37C. Absolute viable cell counts were assayed with counting beads (TruCOUNT, BD, CA) and propidium iodide (PI) staining (Sigma) using a FACSCalibur (BD) and CellQuest Pro software (BD). CDC was determined by comparing counts to CLL cells treated with NHS alone. Membrane levels of CD59, bound MoAb, and deposited C3b on the CLL cells membranes were measured by flow cytometry using using the anti-CD59 antibody FITC-CD59 (BD), mouse anti-human Fc antibody FITC-HB43, and the anti-C3b antibody FITC-7C12. To study ALEM CDC resistant cells, CLL cells were first treated with ALEM and NHS as detailed above. Surviving viable cells were isolated using density gradient centrifugation and then retreated. C5 deficient serum (Sigma) was used in experiments to determine MoAb binding and C3b deposition in the entire CLL cell population. Results: Binding of either ALEM or OFA to the CLL cells in NHS resulted in activation of complement and deposition of large amounts of membrane C3b on the cells. However, ALEM induced higher levels of C3b deposition (delta MFI 220) and caused more CDC (73% vs. 18%) compared to OFA. This correlated well with the higher levels of expression of CD52 vs. CD20 expression in CLL cells (143 ×103, range 131 ×103 – 159 ×103 vs. mean 20 ×103 molecules/cell, range 10 ×103 – 28 ×103). Studies with the anti-Fc antibody showed that only a small subpopulation of CLL cells had weak MoAb binding. Addition of OFA to ALEM increased complement-mediated C3b deposition. In three patients with high initial ALEM CDC, addition of OFA did not appreciably increase CDC (81% to 87%). However, in one patient with cells that were less sensitive to ALEM CDC, addition of OFA did appreciably increase CDC (51% to 86%). There was no relationship between levels of CD59 expression and CDC. All four CLL specimens studied contained a subpopulation of cells that were resistant to CDC (mean 13%, range 9–18%) despite robust C3b deposition. Conclusions: These data suggests that there are multiple mechanisms of resistance to MoAb-mediated CDC including: 1. Low MoAb binding because of low target antigen expression; 2. Insufficient C3b deposition after MoAb ligation and; 3. Intrinsic resistance in some cells in cells in which high levels of C3b deposition were clearly demonstrable. OFA can increase MoAb binding, C3b deposition, and CDC in CLL cells treated with ALEM. However, addition of OFA does not overcome the intrinsic resistance of a small subpopulation of CLL cells to CDC. Future studies will be needed to examine these resistance mechanisms and to develop interventions to disrupt them. In addition, membrane C3b could be a target for complement dependent cellular cytotoxity in these CDC resistant cells. Disclosures: Taylor: G.S.K.: Research Funding; Genmab: Research Funding. Zent:Genzyme: Research Funding; Genentech: Research Funding; Novartis: Research Funding; G.S.K.: Research Funding.

Abstract Background: We previously reported that Lenalidomide combined with R-CHOP (R2CHOP) has significant activity in non-GCB (non-germinal center B-cell) subtype of DLBCL as defined by immunohistochemistry (IHC) using Hans algorithm (J Clin Oncol. 2015 Jan 20;33(3):251-7). However, defining non-GCB subtype of DLBCL by IHC as opposed to the "gold standard" gene expression profiling (GEP) is subject to technical limitations and its prognostic value has not reproduced in some recently published studies. In addition, recent reports questioned prognostic value of GEP in prospective clinical trials as opposed to initial reports from retrospective case series. To address these concerns, we assessed outcomes by cell of origin (COO) as determined via GEP using NanoString Lymphoma Subtyping Test (LST) on formalin-fixed paraffin-embedded (FFPE) tissue on patients enrolled in a phase 2 study of R2CHOP and an independent comparison cohort of patients treated with RCHOP alone. Methods: Eligible patients for R2CHOP phase 2 study MC078E were adults with newly diagnosed, untreated, stages II-IV CD20 positive DLBCL. Patients received oral lenalidomide 25 mg days 1-10 with standard dose R-CHOP every 21 days for 6 cycles. All patients received pegfilgrastim on day 2 of each cycle and aspirin prophylaxis. DLBCL molecular subtype was determined by GEP using NanoString LST, a multiplexed digital gene expression assay performed on the nCounter® Dx Analysis System and reported as GCB vs ABC vs unclassified. A comparison cohort of RCHOP treated DLBCL patients was generated from the prospectively enrolled Mayo Clinic component of the Lymphoma SPORE Molecular Epidemiology Resource (MER). MER patients meeting the same inclusion criteria as MC078E with available tissue were selected based via matching on age, stage, and IPI to the MC078E patients. Event-free survival was defined as time from diagnosis (MER) or study registration (MC078E) to progression, re-treatment, or death. EFS24 was defined as being event-free at 24 months. Associations between COO and outcome were assessed via log-rank tests due to censoring for EFS24. Results: 50 MC078E R2CHOP patients enrolled between 2008 and 2013,124 matched MER RCHOP patients diagnosed between 2003 and 2012 were assessed for COO. Median follow up in 70 patients still alive was 7.9 years (1.9-13.0) in RCHOP treated patients and 4.4 years (1.9-5.5) for 24 in R2CHOP treated patients still alive. Median age was 65 years (range 35-89) in RCHOP treated patients and 69 years (22-87) in R2CHOP patients (p=0.485). 53 RCHOP treated patients (43%) and 31 R2CHOP treated patients (62%) had intermediate-high or high IPI (p=0.021). COO was GCB, ABC, and unclassified DLBCL subtype in 80, 31 and 13 patients in the 124 RCHOP cohort and 33, 13 and 4 patients in the R2CHOP treated patients, respectively (see table). EFS24 was inferior for ABC (48%) compared to GCB DLBCL 71% in MER RCHOP treated patients (p=0.013). In contrast, in R2CHOP treated pts, EFS24 was not different between ABC vs GCB DLBCL 69% vs 67% (p= 0.674). Conclusion: Cell of origin classification of DLBCL determined by NanoString LST remains prognostic in a series of prospectively enrolled DLBCL patients treated with RCHOP. R2CHOP shows promising efficacy in ABC DLBCL as defined by NanoString LST, where the addition of lenalidomide to RCHOP appears to mitigate the negative impact of an ABC molecular subtype on the outcome. Table Table. Disclosures Nowakowski: Morphosys: Research Funding; Bayer: Consultancy, Research Funding; Celgene: Research Funding. Maurer:Kite Pharma: Research Funding; Celgene: Research Funding. Storhoff:NanoString Technologies, Inc.: Employment, Other: Stock option. Dennis:NanoString Technologies, Inc.: Employment, Other: Stock option. Gandhi:Celgene Corporation: Employment, Equity Ownership. Thakurta:Celgene: Employment, Equity Ownership. Hagner:Celgene Corporation: Employment, Equity Ownership. Rimsza:NCI/NIH: Patents & Royalties: L.M. Rimsza is a co-inventor on a provisional patent, owned by the NCI of the NIH, using Nanostring technology for determining cell of origin in DLBCL..

Abstract Background Central nervous system (CNS) relapse of diffuse large B-cell lymphoma (DLBCL) is a devastating event occurring in approximately 5% of patients treated with standard R-CHOP (Thanarajasingam et al, ASH 2015, abs 1456). Isolated CNS relapse is associated with significant morbidity and mortality. New treatment regimens with agents that cross the blood-brain barrier (BBB) are needed. The combination of lenalidomide with R-CHOP (R2CHOP) has shown promising results in activated B-cell (ABC) type DLBCL in phase 2 studies and is currently being evaluated in randomized trials. Lenalidomide crosses the BBB and has been demonstrated to have single-agent activity in relapsed CNS lymphoma. Accordingly, the addition of lenalidomide to R-CHOP may decrease the risk of CNS relapse. Here we characterize the combined incidence of isolated CNS relapse in a population of DLBCL patients who received R2CHOP for induction therapy in two independent phase 2 studies. Methods We analyzed the incidence of isolated CNS relapse in patients with histologically-confirmed DLBCL enrolled in two R2CHOP phase 2 trials - one conducted by Mayo Clinic (MC) and the other by Italian Lymphoma Foundation (FIL) - in the context of clinical variables that included age, gender, disease stage, cell of origin, and administration of CNS prophylaxis. We assessed CNS-International Prognostic Index (CNS-IPI) factors (age, stage, lactate dehydrogenase level, ECOG performance status, extranodal sites, adrenal/kidney involvement) and classified patients into groups of low, intermediate, and high risk of CNS relapse. The risk of CNS relapse in R2CHOP-treated patients was then estimated and compared against published rates in RCHOP-treated patients based on CNS-IPI score. Results One hundred thirty-six patients with DLBCL from both cohorts (87 MC patients, 49 FIL patients) were included in this analysis. Mean age was 65 and median follow-up in 104 patients still alive was 48.2 months (range: 2.1-88.5). 61.8% of patients were male; 86.0% had stage III disease or higher; 44.1% had ECOG performance status of 0; cell of origin phenotype by immunohistochemistry according to Hans algorithm was germinal center B-cell (GCB), non-GCB (ABC), and not available in 43.4%, 36.8%, and 19.8%, respectively; 14.7% received intrathecal (IT) methotrexate for CNS prophylaxis per local practice. No patients received intravenous methotrexate. 10.3%, 71.3%, and 18.4% of patients were classified into low, intermediate, and high-risk CNS-IPI groups, respectively. Only one of 136 patients developed isolated CNS relapse, corresponding to an estimated incidence of CNS relapse of 0.007 (0.7%). Conclusions Despite a large proportion of patients with intermediate and high risk of CNS relapse treated in both phase 2 studies, induction therapy with R2CHOP in patients with DLBCL is associated with a lower-than-expected rate of isolated CNS relapse. The latter is unlikely to be explained by use of IT chemotherapy, which is considered to be marginally effective in this setting and was implemented only in a small proportion of patients. This suggests that addition of CNS-penetrating small molecules, such as lenalidomide, to R-CHOP may decrease the risk of CNS relapse. Disclosures Chiappella: Celgene: Speakers Bureau; Teva: Speakers Bureau; Roche: Speakers Bureau; Pfizer: Speakers Bureau; Janssen-Cilag: Speakers Bureau; Amgen: Speakers Bureau. Nowakowski:Morphosys: Research Funding; Celgene: Research Funding; Bayer: Consultancy, Research Funding. Cavallo:Janssen-Cilag: Honoraria; Onyx: Honoraria; Celgene: Honoraria. Gaidano:Roche: Consultancy, Honoraria, Speakers Bureau; Karyopharm: Consultancy, Honoraria; Morphosys: Consultancy, Honoraria; Gilead: Consultancy, Honoraria, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau; Novartis: Consultancy, Honoraria, Speakers Bureau. Spina:Mundipharma: Membership on an entity's Board of Directors or advisory committees, Other: Speaker Fee; Teva Pharmaceuticals Industries: Membership on an entity's Board of Directors or advisory committees, Other: Speaker Fee. Vitolo:Takeda: Other: Honoraria for lectures; Gilead: Other: Honoraria for lectures; Janssen: Membership on an entity's Board of Directors or advisory committees, Other: Honoraria for lectures; Roche: Membership on an entity's Board of Directors or advisory committees, Other: Honoraria for lectures.

Abstract Background: Diffuse large B-cell lymphoma (DLBCL) is curable for the majority of patients treated with anthracycline based immunochemotherapy (IC). However, up to 40% of patients will relapse or require retreatment of DLBCL and outcomes are poor in this setting. Here we examine the incidence, treatment patterns and outcomes of relapsed DLBCL in the R-CHOP era. Methods: Patients were prospectively enrolled in the University of Iowa / Mayo Clinic SPORE Molecular Epidemiology Resource (MER) within 9 months of diagnosis and followed for relapse, retreatment, and death. Clinical management at diagnosis and subsequent therapies were per treating physician. This analysis includes patients with DLBCL or primary mediastinal B-cell lymphoma (PMBCL) who underwent front-line anthracycline based IC; patients with primary CNS lymphoma or PTLD were excluded. All relapse and re-treatments were verified by medical record review. Response to front-line therapy was retrospectively classified per 2007 Revised Response Criteria for Malignant Lymphoma from available clinical and radiology records. Unplanned consolidative radiation (RT) without biopsy proven disease after achieving PR from IC (N=21) was not classified as a relapse. Results: 1039 patients with newly diagnosed DLBCL or PMBCL and treated with IC were enrolled in the MER from 2002-2012. Median age at diagnosis was 62 years (range 18-92) and 577 patients (56%) were male. 647 patients (63%) had stage III/IV disease and IPI at diagnosis was 0-1 in 350 patients (34%), 2 in 305 patients (29%), 3 in 250 patients (24%) and 4-5 in 134 patients (13%). At a median follow-up of 59 months (range 1-148), 258 patients had relapse or retreatment of DLBCL of which 184 (71%) died. Incidence of relapse was 21.7% (95% CI: 19.3%-24.4%) at 2 years and 25.5% (95% CI: 22.9%-28.5%) at 5 years. In addition, the incidence of lymphoma related death without documented relapse or retreatment was 4.7% (95% CI: 3.6%-6.2%) at 2 years. At first relapse, 174 patients (67% of relapsed) received platinum based salvage therapy with 90 (52%) subsequently proceeding to autologous stem cell transplant (ASCT). 22 patients received CNS directed systemic therapy at relapse with 9 (41%) proceeding to transplant, and 43 received non-platinum-based salvage systemic therapy with 7 proceeding to transplant (17%), 15 patients received RT only as 2nd line therapy, and 4 were untreated. At a median follow-up of 56 months (range 6-121) post-transplant, 39 of 107 patients who underwent transplant remain in remission with a 2-year post-transplant progression-free survival of 45% (95% CI 37%-56%). Response to front-line IC was predictive of post-relapse outcome. Survival post-relapse was superior in the 162 patients with responsive disease (CR or PR) at the end of front-line IC (median OS 21.0 months) compared to the 88 patients who had stable or progressive disease (median OS 6.8 months, HR = 2.33, 95% CI: 1.73-3.14 p<0.0001). Transient response in midst of front-line IC was similar to no response. Patients achieving a CR or PR to front-line IC were more likely to proceed to ASCT at relapse (55%) compared to patients with either SD or PD at the end of front-line IC (25% and 17% respectively, p<0.0001). Other factors associated with poor survival at first relapse were relapse within 12 months of diagnosis (HR = 2.24, 95% CI: 1.57-3.18, p<0.0001), IPI at diagnosis of 3-5 (HR=1.51, 95% CI: 1.13-2.03, p=0.0058), and age > 60 (HR =1.51, 95% CI: 1.12-2.03, p=0.0064). There was no difference in survival at first relapse by cell of origin (HR = 1.13, 95% CI: 0.74-1.72, p=0.59). Conclusions: Most patients undergo therapy after relapsed/refractory DLBCL but only one-third receive ASCT. Outcomes following all treatments for relapsed/refractory DLBCL remain poor. Factors associated with adverse outcomes include refractory to front-line therapy, early relapse, baseline IPI and advanced age. These outcomes provide relevant historical control for the many novel agents being tested in this unmet need. Figure 1. Figure 1. Disclosures Farooq: Kite Pharma: Research Funding. Maurer:Kite Pharma: Research Funding. Cerhan:Kite Pharma: Research Funding. Link:Genentech: Consultancy, Research Funding; Kite Pharma: Research Funding. Thompson:Kite Pharma: Research Funding.

Abstract Abstract 1926 Background: Follicular lymphoma (FL) is the second most common non Hodgkin lymphoma in the United States, comprising up to 30% of all non Hodgkin lymphomas. Typically an indolent disease, relapses are common. High dose therapy followed by autologous stem cell transplant is an option that has shown to produce prolonged progression-free and relapse-free survival in patients who relapse. Adequate bone marrow reserve for peripheral stem cell mobilization has been shown to be adversely effected by prior regimens such as fludarabine and radioimmunotherapy. Concerns regarding stem cell mobilization at the point of relapse have led some to collect stem cells early in the course of disease to allow for potential subsequent transplant after relapse. Recent advances in stem cell mobilization have resulted in a 3% collection failure rate for lymphoma patients at the point of planned transplant at our institution versus a historical rate of up to 30%. We studied the utilization of stem cells collected for potential future use in FL patients in remission or prior to therapy at the point of relapse or progression in order to determine the utility of this approach. Methods: Record review of patients diagnosed with FL through the Mayo Clinic Tumor Registry and the Mayo Clinic Lymphoma Data Base who had cryopreserved stem cells for potential future transplant at relapse. Cost of stem cell storage at our institution was reviewed as was the subsequent use of the collected cells. Results: 73 patients with FL had stem cells collected and stored. 37 (51%) were collected prior to a double dose yttrium-90 (90Y) ibritumomab tiuxetan trial for relapsed lymphoma as required by the study. The median age at collection of this group was 56 years (range 28–70). Stem cells remain in storage for a median of 44 months (range 8–119). The median cost of cryopreservation and storage is $4,094 based on the median storage time of 44 months (range $3,628 to 5,065) with a collection cost of $3,524.20 and an annual storage fee of $155.39. This does not include the cost of filgrastim for mobilization, nor line placement. At 5 years, 60% of the cells were not utilized, and at 10 years, 56% of the cells were not utilized. 36 (49%) of the total number of patients were not part of the double dose 90Y ibritumomab tiuxetan trial, but were collected in remission for possible future use or in the setting of relapsed, progressed or transformed disease for potential future transplant. Five of these patients required the use of plerixafor for adequate mobilization. The median age at collection of this group was 47 years (range 24–76). Stem cells remain in storage for a median of 39 months (range 2–128). The median cost of cryopreservation and storage is $4,029 based on the median storage time of 39 months (range $3,550 to 5,182) with a collection cost of $3,524.20 and an annual storage fee of $155.39. This does not include the cost of filgrastim or plerixafor for mobilization, nor line placement. At 5 years, 89% of these cells were not used, and at 10 years, 71% of cells were not used. Conclusion: The utilization of stem cells collected early in the course of FL patients is low, with the majority of cells not being utilized at 10 years. Given improved mobilization techniques resulting in 97% efficacy of stem cell collection at relapse, routine collection and storage of stem cells early in the course FL is not recommended. Disclosures: Micallef: Genzyme: Membership on an entity's Board of Directors or advisory committees, Research Funding.

Abstract Abstract 4168 Background: Primary Pulmonary MALT lymphoma represents 15–20% of Extranodal Marginal Zone Lymphomas of Mucosa Associated Lymphoid Tissue (MALT). In contrast to the more common gastric MALT lymphoma, natural history, prognosis and treatment outcomes for primary pulmonary MALT lymphoma are not well defined. Herein, we report a single institution experience. Methods: Consecutive patients with primary pulmonary MALT lymphoma registered in the Mayo Clinic Lymphoma Database, which includes all consenting patients with lymphoma seen at Mayo Clinic Rochester, were reviewed for clinical features, treatment outcome progression free survival (PFS) and overall survival (OS). The pathology for all patients was centrally reviewed by hematopathologist and the diagnoses were based on WHO lymphoma classification criteria. PFS and OS were assessed using the Kaplan–Meier method and the Cox proportional hazard model was used to assess the impact of variables on PFS and OS. Results: Between December 1986 and June of 2009, ninety-seven patients with primary pulmonary MALT lymphoma were enrolled. The median age at diagnosis was 63 years (range 31–87). There were 43 (44%) males. The initial presentation was a unilateral pulmonary lesion (n=47, 48%), bilateral pulmonary lesions (n=41, 42%), and pulmonary lesion with intrathoracic lymphadenopathy (n= 4, 4%). Bone marrow involvement and presence of B symptoms were 4, 4% and 5, 5%, respectively. International Prognostic Index (IPI) was 0–1, 2–3 and 4–5 in 69, 25 and 1 patient(s) respectively. The median follow-up was 10.4 years. The estimated median OS was 13. 6 years and the median PFS was 5.5 years (Figure). In a multivariate analysis, age >60 (p=0.02) and ECOG PS>2 (p=0.01) were associated with shortened survival. The IPI and age adjusted IPI were not predictive of overall survival. The treatment outcomes for the most common treatment modalities are summarized in the Table below. The median PFS of the 38% of patients who had a complete surgical resection was excellent at 11.2 years; whereas for observed patients with residual disease after biopsy was 3.2 years. Only 8 patients received single agent rituximan with relatively low response rate. Summary: The prognosis of primary pulmonary MALT lymphoma is favorable, with a median survival of over 13 years. In patients with resectable disease, surgery alone is associated with excellent disease control. Further prospective studies are needed to define the optimal treatment of primary pulmonary MALT lymphoma. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 3088 Background: Despite the use of modern immunochemotherapy (R-CHOP) regimens, almost 50% of patients with diffuse large-B-cell lymphoma (DLBCL) will relapse. Current prognostic models, most notably the International Prognostic Index, are comprised of patient and tumor characteristics and are unable to identify patients with less than a 50% chance of long-term survival. However, recent observations demonstrate that factors related to host adaptive immunity and the tumor microenvironment are powerful prognostic variables in non-Hodgkin lymphoma Methods: We retrospectively examined the absolute neutrophil count (ANC), monocyte count (AMC) and lymphocyte count (ALC), obtained from an automated complete blood count with differential, as prognostic variables in a cohort of 255 consecutive DLBCL patients that were uniformly treated with R-CHOP between 2000 and 2007 at a single institution. The primary study objective was to assess if ANC, AMC, and ALC at diagnosis were predictors of overall survival (OS) in DLBCL. Results: At diagnosis, the median ANC was 4720/uL (range 1190–17690), the median AMC was 610/uL (range 30–4040), and the median ALC was 1220/uL (range 140–5410). The median follow-up for these patients was 48 months. In the univariate analysis, each of these variables predicted OS as continuous variables. As dichotomized variables, an elevated ANC (≥5500/μL; hazard ratio 1.75, 95% confidence interval 1.14–2.60, p=0.01) and AMC (≥610/μL; hazard ratio 3.36, 95% confidence interval 2.10–5.59, p<0.0001) were each associated with inferior OS. In contrast, the presence of lymphopenia, defined as an ALC ≤1000/uL, was associated with inferior OS (hazard ratio 2.21, 95% confidence interval 1.43–3.39, p=0.0004). When components of the IPI were included on multivariate analysis only the AMC and ALC were independently significant prognostic factors for OS, with hazard ratios of 3.37 (95% confidence interval 2.05–5.74, p<0.0001) and 2.19 (95% confidence interval 1.38–3.44, p=0.0009), respectively. The dichotomized AMC and ALC generated the AMC/ALC prognostic index (PI) and stratified patients into 3 risk groups: very good (AMC <610/uL and ALC >1000/uL), good (AMC ≥610/uL or ALC ≤1000/uL), and poor-risk (AMC ≥610/uL and ALC ≤1000/uL) populations. For both the very good (n=79) and good-risk (n=134) groups median OS has not been reached with estimated 5-year overall survival of 88% and 69%, respectively. Median OS for poor-risk (n=42) patients was 1.7 years (95% confidence interval 1.1–2.7 years) with an estimated 5-year overall survival of 28% (p<0.0001). By comparison, the R-IPI was unable to identify a group of patients with a median survival less than 8 years. The estimated 5-year OS was 93%, 71% and 53% for very good, good and poor-risk patients, respectively. We sought to determine whether the AMC/ALC PI may provide additional prognostic information when combined with the R-IPI. To test this possibility, the 171 very good/good risk and 84 poor risk patients identified by the R-IPI were subsequently risk stratified using the AMC/ALC PI. Among R-IPI very good/good risk patients a subset of poor risk patients (n=21) with a median OS of 2.2 years (95% confidence interval 1.1–6.6 years) and 35% 5-year OS could be identified with the AMC/ALC PI. In contrast, 5-year OS ranged from 75%-88% among very good and good risk patients. Similarly, stratification of R-IPI poor risk patients by the AMC/ALC PI identified subsets of very good (n=19) and good risk (n=44) patients with median OS that had not been reached and 86% and 55% 5-year OS, respectively. High risk (n=21) patients had a median OS of 1.4 years (95% confidence interval 0.9–2.2 years) and an estimated 5-year OS of less than 25%. Conclusions: Measurement of AMC and ALC at diagnosis is widely applicable, cost effective, predicts OS, and identifies high-risk patients with DLBCL. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 2802 Background: Redundancy of pro-survival signaling pathways promotes survival and drug resistance in lymphoid and plasma cell malignancies. In particular, the PI3K-Akt and the MEK-ERK pathways have been shown to play an important role in the proliferation and survival of these malignant cells induced by various cytokines in the tumor microenvironment. Sorafenib, a Raf kinase and VEGF receptor inhibitor, and everolimus, an mTOR inhibitor, have synergistic cytotoxicity in myeloma and lymphoma cells due to inhibition of multiple signaling pathways. Methods: We designed a Phase 1/2 clinical trial to identify the maximum tolerated doses of the two drugs used in combination and the efficacy of the combination. Patients (Pts) with relapsed myeloma or lymphoma were eligible for enrollment. Pts were required to have an absolute neutrophil count ≥1500 × 10(6)/L, a platelet count ≥75,000, and a serum creatinine 21.5 mg/dL. The study utilized the classic 3+3 design. Extensive pharmacokinetic studies were performed to better delineate potential drug interactions. Results: Twenty-six pts were accrued from August 2007 to February 2009. Four pts discontinued sorafenib during cycle 1 for various reasons (2 patient refusal, 1 unrelated medical condition and 1 physician discretion) and were excluded from MTD determination. An additional pt did not have measurable disease and was ineligible, leaving 19 pts with lymphoma (including 6 with Hodgkin lymphoma) and 2 with myeloma for phase I analysis. The pts had a median age of 56 years (range, 22, 69) and were heavily pretreated with a median of 4 prior therapies (range, 1–10). Eighteen (86%) had received a prior stem cell transplant. Four dose limiting toxicities were seen across all dose levels (Table). These included grade 3 vomiting (level 1), grade 4 thrombocytopenia (level 2 and 3, one each) and grade 2 hand and foot rash leading to treatment delay (level 3). Overall, 13 pts experienced a grade 3 or 4 hematologic toxicity. Grade 3 or 4 anemia, neutropenia, and thrombocytopenia occurred in 19%, 43%, and 38% of pts, respectively. Four pts have experienced a grade 3 non-hematologic toxicity; no grade 4 non-hematologic toxicities were seen. Grade 3 non-hematologic toxicities included hypokalemia, weight loss, vomiting, hand-foot skin reaction, fatigue, and elevated alkaline phosphatase. Dose level 1 (sorafenib 200 mg and everolimus 5 mg daily) was best tolerated and was selected for phase 2 evaluation. The ORR was 33% (7/21;95% CI: 15–57%, Table) with 3 pts at dose level 0 (2 PR, 1 CR), one at level 2 (1 PR) and three at level 3 (2 PR, 1 CR) responding. The responders included 5 pts with Hodgkin's disease and one each with an NK cell and T-cell lymphoma. Pts have received a median of 6 cycles (range: 1–19) of treatment. 16 pts have discontinued treatment due to disease progression (13 pts), non-resolution of cytopenias (1 pt), physician discretion (1 pt), and death on study due to lymphoma (1 pt). Disease progression has been seen in 16 pts; 9 pts have died. Median follow-up for pts still alive is 18.7 months (range: 11.5–29.4). 6 pts died from disease progression, one each due to sepsis unlikely related to treatment, cholecystitis, and unknown causes. Sorafenib is metabolized by the cytochrome P450 CYP3A enzyme and RAD-001 mainly by the CYP3A4 system in the liver, hence there is a potential for interactions. The detailed PK analyses performed as part of this trial showed a decrease in the RAD001 levels following initiation of sorafenib on day 8 of cycle 1 (Figure). Conclusion: The combination of sorafenib and everolimus is safe at a recommended phase 2 dose of sorafenib 200 mg and everolimus 5 mg daily. There is no significant drug interaction seen. Activity has been observed, especially in the setting of Hodgkins Disease. Disclosures: Kumar: Celgene: Consultancy, Research Funding; Millennium: Research Funding; Merck: Consultancy, Research Funding; Novartis: Research Funding; Genzyme: Consultancy, Research Funding; Cephalon: Research Funding. Off Label Use: Lenalidomide for treatment of newly diagnosed myeloma. Witzig:Novartis and Celgene: Patents & Royalties, Research Funding, Served on advisory boards with Novartis and Celgene – both uncompensated with compensation to Mayo Clinic.